Sony's lated MD portable recorders DO (at last) allow uploading of recorded material to your computer via USB.
See the MZ-NH700 (www.minidisc.org) for example, and I think the others in that family do the same.

It's HI-MD too, which means it can use high capacity disks which are 1Gb instead of the standard 144Mb, so about 7 times the playing time, and it reformats standard MDs to double capacity too, if I've understood and remembered correctly.

Anahata